A wheeled rack which has general utility in handling mail, or other articles, is described in Patent Application Ser. No. 477,805, which was filed June 10, 1974. The wheeled rack described in the patent application is constructed to carry trays of mail, with the trays being slidably tiered on rails within the rack. The rack has particular utility for carrying trays of sorted, or partially sorted mail from a main post office to substation post offices, and for carrying bags of unsorted mail back from the sub-station post offices to the main post offices.
A retainer bar assembly is described in U.S. Pat. No. 3,902,603 which issued Sept. 2, 1975 to the present inventor, which constitutes a simple mechanism which may be moved between a closed position and an open position. When the retainer bar assembly is in its closed position, it prevents the trays from falling out of the front of the rack, as the rack is transported from one location to another.
The retainer bar assembly of the present invention is generally similar to the retainer bar assembly described and claimed in the patent. However, the retainer bar assembly of the present invention is simpler and more effective than the previous assembly.